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RFC 1213 - 6.6. The IP Group

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### 6.6. The IP Group

              -- the IP group

              -- Implementation of the IP group is mandatory for all
              -- systems.

              ipForwarding OBJECT-TYPE
                  SYNTAX  INTEGER {
                              forwarding(1),    -- acting as a gateway
                              not-forwarding(2) -- NOT acting as a gateway
                          }
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The indication of whether this entity is acting
                          as an IP gateway in respect to the forwarding of
                          datagrams received by, but not addressed to, this
                          entity.  IP gateways forward datagrams.  IP hosts
                          do not (except those source-routed via the host).

                          Note that for some managed nodes, this object may
                          take on only a subset of the values possible.
                          Accordingly, it is appropriate for an agent to
                          return a `badValue' response if a management
                          station attempts to change this object to an
                          inappropriate value."
                  ::= { ip 1 }

              ipDefaultTTL OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The default value inserted into the Time-To-Live
                          field of the IP header of datagrams originated at
                          this entity, whenever a TTL value is not supplied
                          by the transport layer protocol."
                  ::= { ip 2 }

              ipInReceives OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The total number of input datagrams received from
                          interfaces, including those received in error."
                  ::= { ip 3 }

              ipInHdrErrors OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of input datagrams discarded due to
                          errors in their IP headers, including bad
                          checksums, version number mismatch, other format
                          errors, time-to-live exceeded, errors discovered
                          in processing their IP options, etc."
                  ::= { ip 4 }

              ipInAddrErrors OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of input datagrams discarded because
                          the IP address in their IP header's destination
                          field was not a valid address to be received at
                          this entity.  This count includes invalid
                          addresses (e.g., 0.0.0.0) and addresses of
                          unsupported Classes (e.g., Class E).  For entities
                          which are not IP Gateways and therefore do not
                          forward datagrams, this counter includes datagrams
                          discarded because the destination address was not
                          a local address."
                  ::= { ip 5 }

              ipForwDatagrams OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of input datagrams for which this
                          entity was not their final IP destination, as a
                          result of which an attempt was made to find a
                          route to forward them to that final destination.
                          In entities which do not act as IP Gateways, this
                          counter will include only those packets which were
                          Source-Routed via this entity, and the Source-
                          Route option processing was successful."
                  ::= { ip 6 }

              ipInUnknownProtos OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of locally-addressed datagrams
                          received successfully but discarded because of an
                          unknown or unsupported protocol."
                  ::= { ip 7 }

              ipInDiscards OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of input IP datagrams for which no
                          problems were encountered to prevent their
                          continued processing, but which were discarded
                          (e.g., for lack of buffer space).  Note that this
                          counter does not include any datagrams discarded
                          while awaiting re-assembly."
                  ::= { ip 8 }

              ipInDelivers OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The total number of input datagrams successfully
                          delivered to IP user-protocols (including ICMP)."
                  ::= { ip 9 }

              ipOutRequests OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The total number of IP datagrams which local IP
                          user-protocols (including ICMP) supplied to IP in
                          requests for transmission.  Note that this counter
                          does not include any datagrams counted in
                          ipForwDatagrams."
                  ::= { ip 10 }

              ipOutDiscards OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of output IP datagrams for which no
                          problem was encountered to prevent their
                          transmission to their destination, but which were
                          discarded (e.g., for lack of buffer space).  Note
                          that this counter would include datagrams counted
                          in ipForwDatagrams if any such packets met this
                          (discretionary) discard criterion."
                  ::= { ip 11 }

              ipOutNoRoutes OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of IP datagrams discarded because no
                          route could be found to transmit them to their
                          destination.  Note that this counter includes any
                          packets counted in ipForwDatagrams which meet this
                          `no-route' criterion.  Note that this includes any
                          datagarms which a host cannot route because all of
                          its default gateways are down."
                  ::= { ip 12 }

              ipReasmTimeout OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The maximum number of seconds which received
                          fragments are held while they are awaiting
                          reassembly at this entity."
                  ::= { ip 13 }

              ipReasmReqds OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of IP fragments received which needed
                          to be reassembled at this entity."
                  ::= { ip 14 }

              ipReasmOKs OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of IP datagrams successfully re-
                          assembled."
                  ::= { ip 15 }

              ipReasmFails OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of failures detected by the IP re-
                          assembly algorithm (for whatever reason: timed
                          out, errors, etc).  Note that this is not
                          necessarily a count of discarded IP fragments
                          since some algorithms (notably the algorithm in
                          RFC 815) can lose track of the number of fragments
                          by combining them as they are received."
                  ::= { ip 16 }

              ipFragOKs OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of IP datagrams that have been
                          successfully fragmented at this entity."
                  ::= { ip 17 }

              ipFragFails OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of IP datagrams that have been
                          discarded because they needed to be fragmented at
                          this entity but could not be, e.g., because their
                          Don't Fragment flag was set."
                  ::= { ip 18 }

              ipFragCreates OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of IP datagram fragments that have
                          been generated as a result of fragmentation at
                          this entity."
                  ::= { ip 19 }

              -- the IP address table

              -- The IP address table contains this entity's IP addressing
              -- information.

              ipAddrTable OBJECT-TYPE
                  SYNTAX  SEQUENCE OF IpAddrEntry
                  ACCESS  not-accessible
                  STATUS  mandatory
                  DESCRIPTION
                          "The table of addressing information relevant to
                          this entity's IP addresses."
                  ::= { ip 20 }

              ipAddrEntry OBJECT-TYPE
                  SYNTAX  IpAddrEntry
                  ACCESS  not-accessible
                  STATUS  mandatory
                  DESCRIPTION
                          "The addressing information for one of this
                          entity's IP addresses."
                  INDEX   { ipAdEntAddr }
                  ::= { ipAddrTable 1 }

              IpAddrEntry ::=
                  SEQUENCE {
                      ipAdEntAddr
                          IpAddress,
                      ipAdEntIfIndex
                          INTEGER,
                      ipAdEntNetMask
                          IpAddress,
                      ipAdEntBcastAddr
                          INTEGER,
                      ipAdEntReasmMaxSize
                          INTEGER (0..65535)
                  }

              ipAdEntAddr OBJECT-TYPE
                  SYNTAX  IpAddress
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The IP address to which this entry's addressing
                          information pertains."
                  ::= { ipAddrEntry 1 }

              ipAdEntIfIndex OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The index value which uniquely identifies the
                          interface to which this entry is applicable.  The
                          interface identified by a particular value of this
                          index is the same interface as identified by the
                          same value of ifIndex."
                  ::= { ipAddrEntry 2 }

              ipAdEntNetMask OBJECT-TYPE
                  SYNTAX  IpAddress
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The subnet mask associated with the IP address of
                          this entry.  The value of the mask is an IP
                          address with all the network bits set to 1 and all
                          the hosts bits set to 0."
                  ::= { ipAddrEntry 3 }

              ipAdEntBcastAddr OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The value of the least-significant bit in the IP
                          broadcast address used for sending datagrams on
                          the (logical) interface associated with the IP
                          address of this entry.  For example, when the
                          Internet standard all-ones broadcast address is
                          used, the value will be 1.  This value applies to
                          both the subnet and network broadcasts addresses
                          used by the entity on this (logical) interface."
                  ::= { ipAddrEntry 4 }

              ipAdEntReasmMaxSize OBJECT-TYPE
                  SYNTAX  INTEGER (0..65535)
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The size of the largest IP datagram which this
                          entity can re-assemble from incoming IP fragmented
                          datagrams received on this interface."
                  ::= { ipAddrEntry 5 }

              -- the IP routing table

              -- The IP routing table contains an entry for each route
              -- presently known to this entity.

              ipRouteTable OBJECT-TYPE
                  SYNTAX  SEQUENCE OF IpRouteEntry
                  ACCESS  not-accessible
                  STATUS  mandatory
                  DESCRIPTION
                          "This entity's IP Routing table."
                  ::= { ip 21 }

              ipRouteEntry OBJECT-TYPE
                  SYNTAX  IpRouteEntry
                  ACCESS  not-accessible
                  STATUS  mandatory
                  DESCRIPTION
                          "A route to a particular destination."
                  INDEX   { ipRouteDest }
                  ::= { ipRouteTable 1 }

              IpRouteEntry ::=
                  SEQUENCE {
                      ipRouteDest
                          IpAddress,
                      ipRouteIfIndex
                          INTEGER,
                      ipRouteMetric1
                          INTEGER,
                      ipRouteMetric2
                          INTEGER,
                      ipRouteMetric3
                          INTEGER,
                      ipRouteMetric4
                          INTEGER,
                      ipRouteNextHop
                          IpAddress,
                      ipRouteType
                          INTEGER,
                      ipRouteProto
                          INTEGER,
                      ipRouteAge
                          INTEGER,
                      ipRouteMask
                          IpAddress,
                      ipRouteMetric5
                          INTEGER,
                      ipRouteInfo
                          OBJECT IDENTIFIER
                  }

              ipRouteDest OBJECT-TYPE
                  SYNTAX  IpAddress
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The destination IP address of this route.  An
                          entry with a value of 0.0.0.0 is considered a
                          default route.  Multiple routes to a single
                          destination can appear in the table, but access to
                          such multiple entries is dependent on the table-
                          access mechanisms defined by the network
                          management protocol in use."
                  ::= { ipRouteEntry 1 }

              ipRouteIfIndex OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The index value which uniquely identifies the
                          local interface through which the next hop of this
                          route should be reached.  The interface identified
                          by a particular value of this index is the same
                          interface as identified by the same value of
                          ifIndex."
                  ::= { ipRouteEntry 2 }

              ipRouteMetric1 OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The primary routing metric for this route.  The
                          semantics of this metric are determined by the
                          routing-protocol specified in the route's
                          ipRouteProto value.  If this metric is not used,
                          its value should be set to -1."
                  ::= { ipRouteEntry 3 }

              ipRouteMetric2 OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "An alternate routing metric for this route.  The
                          semantics of this metric are determined by the
                          routing-protocol specified in the route's
                          ipRouteProto value.  If this metric is not used,
                          its value should be set to -1."
                  ::= { ipRouteEntry 4 }

              ipRouteMetric3 OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "An alternate routing metric for this route.  The
                          semantics of this metric are determined by the
                          routing-protocol specified in the route's
                          ipRouteProto value.  If this metric is not used,
                          its value should be set to -1."
                  ::= { ipRouteEntry 5 }

              ipRouteMetric4 OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "An alternate routing metric for this route.  The
                          semantics of this metric are determined by the
                          routing-protocol specified in the route's
                          ipRouteProto value.  If this metric is not used,
                          its value should be set to -1."
                  ::= { ipRouteEntry 6 }

              ipRouteNextHop OBJECT-TYPE
                  SYNTAX  IpAddress
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The IP address of the next hop of this route.
                          (In the case of a route bound to an interface
                          which is realized via a broadcast media, the value
                          of this field is the agent's IP address on that
                          interface.)"
                  ::= { ipRouteEntry 7 }

              ipRouteType OBJECT-TYPE
                  SYNTAX  INTEGER {
                              other(1),        -- none of the following

                              invalid(2),      -- an invalidated route
                                               -- route to directly
                              direct(3),       -- connected (sub-)network

                                               -- route to a non-local
                              indirect(4)      -- host/network/sub-network
                          }
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The type of route.  Note that the values
                          direct(3) and indirect(4) refer to the notion of
                          direct and indirect routing in the IP
                          architecture.

                          Setting this object to the value invalid(2) has
                          the effect of invalidating the corresponding entry
                          in the ipRouteTable object.  That is, it
                          effectively dissasociates the destination
                          identified with said entry from the route
                          identified with said entry.  It is an
                          implementation-specific matter as to whether the
                          agent removes an invalidated entry from the table.
                          Accordingly, management stations must be prepared
                          to receive tabular information from agents that
                          corresponds to entries not currently in use.
                          Proper interpretation of such entries requires
                          examination of the relevant ipRouteType object."
                  ::= { ipRouteEntry 8 }

              ipRouteProto OBJECT-TYPE
                  SYNTAX  INTEGER {
                              other(1),       -- none of the following

                                              -- non-protocol information,
                                              -- e.g., manually configured
                              local(2),       -- entries

                                              -- set via a network
                              netmgmt(3),     -- management protocol

                                              -- obtained via ICMP,
                              icmp(4),        -- e.g., Redirect

                                              -- the remaining values are
                                              -- all gateway routing
                                              -- protocols
                              egp(5),
                              ggp(6),
                              hello(7),
                              rip(8),
                              is-is(9),
                              es-is(10),
                              ciscoIgrp(11),
                              bbnSpfIgp(12),
                              ospf(13),
                              bgp(14)
                          }
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The routing mechanism via which this route was
                          learned.  Inclusion of values for gateway routing
                          protocols is not intended to imply that hosts
                          should support those protocols."
                  ::= { ipRouteEntry 9 }

              ipRouteAge OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of seconds since this route was last
                          updated or otherwise determined to be correct.
                          Note that no semantics of `too old' can be implied
                          except through knowledge of the routing protocol
                          by which the route was learned."
                  ::= { ipRouteEntry 10 }

              ipRouteMask OBJECT-TYPE
                  SYNTAX  IpAddress
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "Indicate the mask to be logical-ANDed with the
                          destination address before being compared to the
                          value in the ipRouteDest field.  For those systems
                          that do not support arbitrary subnet masks, an
                          agent constructs the value of the ipRouteMask by
                          determining whether the value of the correspondent
                          ipRouteDest field belong to a class-A, B, or C
                          network, and then using one of:

                               mask           network
                               255.0.0.0      class-A
                               255.255.0.0    class-B
                               255.255.255.0  class-C
                          If the value of the ipRouteDest is 0.0.0.0 (a
                          default route), then the mask value is also
                          0.0.0.0.  It should be noted that all IP routing
                          subsystems implicitly use this mechanism."
                  ::= { ipRouteEntry 11 }

              ipRouteMetric5 OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "An alternate routing metric for this route.  The
                          semantics of this metric are determined by the
                          routing-protocol specified in the route's
                          ipRouteProto value.  If this metric is not used,
                          its value should be set to -1."
                  ::= { ipRouteEntry 12 }

              ipRouteInfo OBJECT-TYPE
                  SYNTAX  OBJECT IDENTIFIER
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "A reference to MIB definitions specific to the
                          particular routing protocol which is responsible
                          for this route, as determined by the value
                          specified in the route's ipRouteProto value.  If
                          this information is not present, its value should
                          be set to the OBJECT IDENTIFIER { 0 0 }, which is
                          a syntatically valid object identifier, and any
                          conformant implementation of ASN.1 and BER must be
                          able to generate and recognize this value."
                  ::= { ipRouteEntry 13 }

              -- the IP Address Translation table

              -- The IP address translation table contain the IpAddress to
              -- `physical' address equivalences.  Some interfaces do not
              -- use translation tables for determining address
              -- equivalences (e.g., DDN-X.25 has an algorithmic method);
              -- if all interfaces are of this type, then the Address
              -- Translation table is empty, i.e., has zero entries.

              ipNetToMediaTable OBJECT-TYPE
                  SYNTAX  SEQUENCE OF IpNetToMediaEntry
                  ACCESS  not-accessible
                  STATUS  mandatory
                  DESCRIPTION
                          "The IP Address Translation table used for mapping
                          from IP addresses to physical addresses."
                  ::= { ip 22 }

              ipNetToMediaEntry OBJECT-TYPE
                  SYNTAX  IpNetToMediaEntry
                  ACCESS  not-accessible
                  STATUS  mandatory
                  DESCRIPTION
                          "Each entry contains one IpAddress to `physical'
                          address equivalence."
                  INDEX   { ipNetToMediaIfIndex,
                            ipNetToMediaNetAddress }
                  ::= { ipNetToMediaTable 1 }

              IpNetToMediaEntry ::=
                  SEQUENCE {
                      ipNetToMediaIfIndex
                          INTEGER,
                      ipNetToMediaPhysAddress
                          PhysAddress,
                      ipNetToMediaNetAddress
                          IpAddress,
                      ipNetToMediaType
                          INTEGER
                  }

              ipNetToMediaIfIndex OBJECT-TYPE
                  SYNTAX  INTEGER
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The interface on which this entry's equivalence
                          is effective.  The interface identified by a
                          particular value of this index is the same
                          interface as identified by the same value of
                          ifIndex."
                  ::= { ipNetToMediaEntry 1 }

              ipNetToMediaPhysAddress OBJECT-TYPE
                  SYNTAX  PhysAddress
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The media-dependent `physical' address."
                  ::= { ipNetToMediaEntry 2 }

              ipNetToMediaNetAddress OBJECT-TYPE
                  SYNTAX  IpAddress
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The IpAddress corresponding to the media-
                          dependent `physical' address."
                  ::= { ipNetToMediaEntry 3 }

              ipNetToMediaType OBJECT-TYPE
                  SYNTAX  INTEGER {
                              other(1),        -- none of the following
                              invalid(2),      -- an invalidated mapping
                              dynamic(3),
                              static(4)
                          }
                  ACCESS  read-write
                  STATUS  mandatory
                  DESCRIPTION
                          "The type of mapping.

                          Setting this object to the value invalid(2) has
                          the effect of invalidating the corresponding entry
                          in the ipNetToMediaTable.  That is, it effectively
                          dissasociates the interface identified with said
                          entry from the mapping identified with said entry.
                          It is an implementation-specific matter as to
                          whether the agent removes an invalidated entry
                          from the table.  Accordingly, management stations
                          must be prepared to receive tabular information
                          from agents that corresponds to entries not
                          currently in use.  Proper interpretation of such
                          entries requires examination of the relevant
                          ipNetToMediaType object."
                  ::= { ipNetToMediaEntry 4 }

              -- additional IP objects

              ipRoutingDiscards OBJECT-TYPE
                  SYNTAX  Counter
                  ACCESS  read-only
                  STATUS  mandatory
                  DESCRIPTION
                          "The number of routing entries which were chosen
                          to be discarded even though they are valid.  One
                          possible reason for discarding such an entry could
                          be to free-up buffer space for other routing
                          entries."
                  ::= { ip 23 }

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RFC 1213 - 6.6. The IP Group